1. Field
The present disclosure generally relates to the field of semiconductor technology, and more particularly, to systems and methods for bonding semiconductor wafers using microwave energy.
2. Description of the Related Art
Application of microwave energy can quickly and effectively bond two semiconductor wafers by localized heating of a metal interlayer between the two wafers. Such localized heating can result from differences in loss tangent values and specific heat capacities.
For such microwave-based bonding process, there are a number of concerns and requirements for obtaining high quality bonds and maintaining the integrity of the semiconductor wafers. For example, compressing the wafers in certain manner can yield a more uniform bonding interface with little or no voids or trapped air pockets. In another example, maintaining certain gaseous condition during the bonding process can reduce the likelihood of oxidation of the wafers. In yet another example, efficient use of the input microwave energy is also desirable.